Arthritis, Osteo

When Ben Franklin said that death and taxes are life's only certainties, he might well have added osteoarthritis to the short list. Osteoarthritis is the complete medical name for the condition generally referred to as "arthritis." When your grandmother complained that her arthritis was bothering her, she was actually suffering from osteoarthritis.

The most common joint disease in humans and all vertebrate animals, osteoarthritis is a universal affliction: virtually everyone who lives past age 75 has it to some degree. Nearly 50 percent of the population suffers from osteoarthritis by age 65.(1)

Known to doctors by the simple acronym "OA," osteoarthritis hits hard on the hardest working joints: the knees, the hips, the hands, and fingers. The weight-bearing joints and the spine are especially vulnerable. It is a fundamental fact of life that as we age, our joints lose their youthful flexibility and range of motion. Movement eventually becomes difficult and painful as we slowly, year by year, become less supple and more stiff.

Sometimes described as "degenerative joint disease" (DJD), osteoarthritis was once thought to result mainly from wear and tear on joints. This traditional theory has been largely abandoned with advances in knowledge of joint physiology. Current thinking is that osteoarthritis is not just a single disorder, but a complex pattern of changes in the repair mechanisms that keep joints functioning normally.(2) A number of different factors can impinge upon the health of joint tissue, including biomechanical forces, changes in body biochemistry, inflammatory processes, and altered immune function.

Osteoarthritis can be classified into two major categories: Primary OA and Secondary OA. Primary OA lacks a specific cause such as trauma or disease. Secondary OA is caused by trauma or some known abnormality such as an infectious disease or endocrine disorder. Primary OA, which reflects the majority of cases, is subdivided into local, general, and erosive OA. Local OA usually affects just one or two joints. In generalized OA, three or more joints are involved. Erosive OA damages the bone around a joint. To arrive at a specific diagnosis, rheumatologists look at factors such as joint pain, visible signs of joint deformity, and changes seen on x-rays and in biochemical tests that detect inflammation.(3)

Cartilage is a metabolically active tissue that is continually being reformed and remodeled. Joint cartilage contains a lot of water-75 to 80 percent by weight-and this water content allows the joint to function as a shock absorber between two adjacent bones. The remaining 20 to 25 percent consists of cells called "chondrocytes" which produce the building material for cartilage, and various structural components.

Collagen, a tough protein fiber, provides the structural backbone for cartilage, somewhat like a reinforcing bar in concrete. Collagen gives cartilage its shape, toughness, and amazing tensile strength. This collagen matrix is filled in with large molecules called "proteoglycans" that have a strong attraction for water. Thanks to proteoglycans and the water they hold, cartilage can bear a tremendous amount of weight. Proteoglycans in turn are made out of long, chain-like molecules called "glycosaminoglycans." Chondroitin sulfate, now popular as a supplement for rebuilding joints, is one of the most important glycosaminoglycans in joint cartilage.

Osteoarthritis is characterized by progressive, degenerative changes in cartilage structure. The proteoglycans break down, losing their ability to form tight clusters. The water content of cartilage increases. Chondroitin sulfate shortens in length. Cartilage loses the ability to repair itself and develops clefts and crevices that eventually extend down to the underlying bone. The end result is weak, stiff, and deformed joints.

World Health Organization, 2000.

• OA is the 4th leading cause of disablilty worldwide.
• Osteoarthritis affects 9.6% of men and 18% of women aged >60 years worldwide.

• More than 20 million people in the United States probably have the disease.
• Some younger people get osteoarthritis from a joint injury, but osteoarthritis most often occurs in older people.
• By age 65, more than half of the population has x-ray evidence of osteoarthritis in at least one joint.
• Since the number of older Americans is increasing, so is the number of people with osteoarthritis.
• Both men and women have the disease.
• Before age 45, more men have it, while after age 45 osteoarthritis is more common in women.

• Physical therapy can help, with specific exercises to improve range of motion and strengthen muscle around the affected joints.
• Weight management is important, as excess body weight puts an added burden on weight-bearing joints.
• NSAIDs, the non-steriodal anti-inflammatory drugs, are the most common medications prescribed for pain relief. These include ibuprofen, ketoprofen, acetaminophen, aspirin, and others. These are available over-the-counter, although a prescription may be needed for higher strengths. These "traditional" NSAIDs are commonly associated with upset stomach, gastro-intestinal bleeding and even the development of gastric ulcers. A new class of NSAIDs have been designed to avoid the stomach and intestinal problems. These drugs are know as COX-2 Inhibitors and are available with a prescription, they include celecoxib and rofecoxib.
• A new form of drug therapy has recently appeared for OA of the knee that injects sodium hyaluronate directly into the knee joint. Hyaluronate, or hyaluronic acid, is a substance found in joint cartilage. This is intended to help reconstitute the synovial fluid, the fluid that lubricates joints. Hyaluronic acid also helps proteoglycans form the clusters that give strength to cartilage. Several published studies have shown this therapy to be helpful in improving joint function.(4),(5),(6)

In OA, the production of glucosamine by the cells that produce the building blocks for cartilage, takes a downturn. Fortunately it can be replaced by glucosamine supplements. Glucosamine has been researched in humans over the last twenty years or so as a treatment for osteoarthritis. Results of controlled trials as well as reports from physicians indicate that glucosamine effectively decreases joint pain and improves joint mobility.(7)

Human studies have given glucosamine in the form of glucosamine sulfate, either orally or by injection into the muscles and joints. While most of these studies have been short-term trials on small numbers of subjects, the results are consistently positive. Taken over a period of two to three months, glucosamine sulfate brings about a gradual reduction in joint pain and tenderness while improving joint flexibility, range of motion, and mobility. In one study, glucosamine sulfate was compared to ibuprofen for pain relief. For the first four weeks ibuprofen was more effective for reducing pain. No surprise there; ibuprofen, after all, is a fast-acting anti-inflammatory medication. By the eighth week of the study, people taking glucosamine sulfate showed greater reductions in pain score than those on ibuprofen. Glucosamine sulfate also caused fewer side effects. Not only that, the benefits of glucosamine sulfate continued for weeks after the study was completed.(8),(9)

Results from a 3-year trial comparing glucosamine to placebo revealed that glucosamine sulfate prevented the progression of the disease based on the amount of free space measured in the joint. It also reduced the frequency and degree of pain. This study suggests that glucosamine sulfate could actually change the progress of the disease and not just the symptoms of it.(10) A similar 3 year study involving 202 people had similar results. All participants had mild to moderate knee osteoarthritis and were given either 1500mg/day of glucosamine sulfate or placebo. In the glucosamine group, the amount of measurable space in the joint did not drastically change whereas the space narrowed in the placebo group. Glucosamine sulfate also significantly improved symptoms compared to placebo. Again the researchers felt as though the decrease in disease progression could possibly indicate modification of the disease process.(11)

The most common dosage of glucosamine is 500mg taken three times daily. Glucosamine hydrochloride, in combination with condroitin sulfate and magnesium has also been found effective. It may take three to four weeks before glucosamine is effective, so stronger anti-inflammatory medication may be necessary for acute conditions for a short period of time.

While the bulk of clinical research studies on chondroitin sulfate have been given by injection, a few trials have tested the oral form as well. In one double-blind study, 800 mg of chondroitin sulfate per day was effective in reducing joint pain and increasing overall mobility. The knee joint space widened, indicating rebuilding of cartilage in the joint. In contrast, subjects taking a placebo showed narrowing of the joint space.(13)

In another double-blind study, 119 patients with osteoarthritis in the fingers took 1200 mg of chondroitin sulfate or a placebo daily for three years. Compared to patients on placebo, those on chondroitin sulfate had much less progression of the disease.(14) In a more long-term trial 80 patients with OA of the knee received 800 mg of chondroitin sulfate or a placebo daily for six months. Subjects taking chondroitin were able to walk longer and needed less pain medication than those on a placebo. Chondroitin sulfate was also very well tolerated.(15)

In a two-year multicenter open trial, SAMe was administered to 108 patients with osteoarthritis of the knee, hip, and spine. The dose was 600mg daily for the first two weeks and then 400mg daily thereafter. The improvement in clinical symptoms--morning stiffness, pain at rest, and pain on movement-- began after the first few weeks of treatment and continued for up to 24 months. SAMe administration also improved the feelings of depression often experienced by people with osteoarthritis.(19)

Side effects occurred in 7.7 percent of patients taking vitamin E compared to 25.9 percent of patients taking diclofenac.

A study involving 56 patients with rheumatoid arthritis, osteoarthritis and muscular discomfort, ginger was effective in more than 75% of the patients.(36) Two-hundred and forty seven patients completed a study lasting 6-weeks evaluating the safety and effectiveness of ginger in osteoarthritis of the knee. The ginger extract group had greater response in reducing knee pain when standing as well as all other measures evaluated. More mild stomach and intestinal upset was experienced by the ginger group. It is important to note that the change in the overall quality of life was equal between the ginger and placebo group.(37) When compared to conventional anti-inflammatory agents, such as ibuprofen, a study found no significant advantage of using ginger root.(38)

• Identify and eliminate food and/or environmental allergies; especially consider the nightshade food group (potato, eggplant, bell pepper).
• Weight control; excess weight increases compression on joint cartilage.
• Water; maximal hydration is imperative since the glycosaminoglycans in the cartilage matrix bind and hold water, which acts like a shock absorber.